Oracle Audio Technologies B31679-01 To see the number and size of the allocated large pages use

The C development tools are required if native development will be done on the machine.

Large pages Large pages can be enabled only if the running Linux kernel supports large pages (also called “huge pages” in Linux community).

If large pages are supported by the kernel, there should be special files in the /proc directory that indicate the number and size of the large pages.

On Linux 2.4.x systems, the /proc/sys/vm/hugetlb_pool indicates the total size of the large pages.

On 2.6.x systems, the /proc/sys/vm/nr_hugepages file indicates the total number of large pages.

You can change the total number and size of the large pages by changing the contents of those files. For example, you can use:

echo "32" > /proc/sys/vm/nr_hugepages

To see the number and size of the allocated large pages use:

cat /proc/meminfo

The following output from this command would indicate that you have

16 large pages, each of the size 256MB for a total of 4GB:

HugePages_Total: 16

HugePages_Free: 16

Hugepagesize: 262144 kB

Note: Since large pages must be allocated on a contiguous memory space, the actual large page size allocated may be smaller than requested. Also, the large page size itself is not configurable. The value of Hugepagesize in /proc/meminfo indicates the system’s fixed large page size.

You may need to change the /etc/security/limits.conf file if PAM (Pluggable Authentication Modules) is enabled.

The OS now is ready for the large page support. To enable this feature on TimesTen, simply set -linuxLargePageAlignment Size_in_MB in the daemon options file (ttendaemon.options).

You should specify the large page alignment size in MB, which is the Hugepagesize value in /proc/meminfo.

Once you set up large pages, TimesTen uses as many large pages as possible. If there are not enough pages, TimesTen uses the normal pages after consuming all available large pages.

28Oracle TimesTen In-Memory Database Installation Guide